"""
Python程序设计语言第4周：循环
示例2：while循环
"""

msg = "Hello, world"
idx = 0
while idx < len(msg):
    print(msg[idx])
    idx = idx + 1


nums = range(10, 0, -1)
idx = 0
while idx < len(nums):
    print(nums[idx])
    idx += 1